Furnace grate



G. G. MARX FURNACE GRATE Sept. 5, 1933.

Filed July 23, 1931 INVENTOR.

GZ'OIPGZ'G: MEX. BY

ATTO EY.

. duced by the deep ribs Patented Sept. 5, 1933 FURNAGE GRATE George G. Marx, Detroit, Mich. Application July 23, 1931. Serial No. 552,686

6 Claims.

This invention relates to furnace grates.

An chest of this invention is a grate comprising a plurality of grate bars, only one of which is disclose-c The bars .e stationary or shakeable, as desired, and. part of a circular grate or a rectangular grate, as desired. The grate bar is provided with deep and with passages and opei gs so arranged that after the air has passed upwardly into openings between the ribs, it will find an exit path, of little resistance, thru the various passages and openings, without its being forced to a path thru the bed of green fuel lying on the bed of burning fuel.

Grate bars with deep ribs are superior to shal-- low bars. In shallow constructions, the lower edges of the bars become heated a great extent and the air, before it enters ti air openings becomes highly heated that it expands to such a degree that amount of oxygen passes thru the air openings in a unit of time, other conditions being similar. Indeep rib constructi IS, the lower edges of the ribs are coniparatively cool and the air finds its way to the air openings withou' bei g expanded to such a deree. Once there, the air passes thru the air openings by virtue of the suction thru them.

When a deep rib bar provided with the openings and. passages of the invention, the effect proon anced considerably, ngs going thru the to the ends of the refrorn, without gothe airwitbin the air 0 various passages and op bars, escaping or existing t ing thru the fuel bed. a

A furt e object is a grate bar having heating chambers, passages, openings so arranged that air travels thru the bars into the heating chambers and passes out of the bars at the ends thereof, causing the fuel near the ends of the bars to burn bes Accordingly, in furnaces provided with water tubes near the ends of the bars, an excellent water heating eifect is produced by a construction of his character, where the fuel is burned est near the ends of the causing the flame to be very 'b e water jackets on the sides, whereas prior art constructions the is usually 12 to 16 inches away from the water in the water iaclset.

Another object'is to produce smokeless combustion by the use of a bar which is so con:- structed that the air passes thru openings in the bar and out, without thru the bed of green fuel on the central portion of the grate. A construction of this character enables to a heavy bed of green fuel on the bur the central portion of the gratawithout creating an impasse against the flow of air, the latter passing thru the heating chanrbe s in the ends of the bars and out through openings in the. side and end walls of said chambers and thence through the thin bed of burning fuel at the edge of the grate.

Further, by virtue of vided by my construction, 1 fuel without diillculty and excessive amount of smoke.

Still further objects will readily occur to those skilled in the art upon reference to the following description and the accompanying drawing in which Fig. 1 is a top plan view of a grate bar.

Figs. 2, 3, i are sections on the lines 2-2; 3-.,; and ea respectively, of Fig. 1.

Referring to the drawing it will be seen that the grate of the invention includes a plurality of parallel, longitudinally extending, deep and elongated ribs 10, separated by parallel, longitudinally extending, ings 12. As best se n in s, the ribs are of comparatively great depth, at least of such a depth that the lower edges of the ribs will not become unduly heated when the grate is operated.

The ends of the ribs and air openings are connected by an end section which is hollow, to provide heating chambersii of substantial volume. These heating chambers are traversed by the passages 16 and are provided with outlet openings 18 in the sides, and openings 20 in the ends of the grate bar. Further, the intermediate cross walls 22 of the chambers are pro vided with passages 24. connectingthe air openings 12 and the chambers. Traversing the ribs 10 is a cross Wall 26 having longitudinally extending passages 28 which connect the ends of adjacent aligned openings 12, for purposes to be described.

The usual supporting lugs 32 and the usual shaker arm 34 may also be provided.

i The distinctive functions of the grate bar disclosed will now be described.

Air passes into the opening 12 and finding its upward path of escape resisted by the heavy bed of green fuel lying on the burning fuel on the grate bar, travels thru the passages 28 and 24 and into the heating chamber 14-, escaping therefrom thru the openings 18 and 20 and thence thru the thin bed of burning fuel at the edge of the grate. Air also passes thru the cored holes 16.

it will be seen that the deep rib effect of the grate bar is considerably enhanced by the provision of the chambers 14 and the air passages. The ordinary deep rib grate bar is superior to the shallow grate bar in that the air does not expand when it strikes the lower edges of the bar but enters the air openings, being withdrawn the positive air flow proy use a low grade lthout creating an therefrom by the suction thru them. This efiect deep and. elongated air open- I since it will be seen that the air in the openings 12 may be withdrawn therefrom thru the openings 24 and 28, into the chambers 14, and out thru the openings 18 and 20. The path thru the chambers 14 offers less resistance than the path thru the heavy beds of green and burning fuel immediately above the bars and accordingly the air in'the openings has a far better path such of escape than would be the case if no chambers were provided.

It will also be seen that the fuel will burn best near the bar ends and accordingly will form flames very near the water jackets at the ends of the bars. I

It will be understood that the grate bar disclosed is not intended to be a complete representation of a commercial product, but has been modified to better illustrate the invention, unhampered by details, not forming a part thereof.

Now having described the invention and the preferred embodiment thereof, it is to be understood that the said invention is to be limited, not to the specificdetails herein set forth, but only by the scope of the claims which follow:

What I claim is:-

1. A grate bar comprising a plurality of spaced deep ribs separated by air openings, cross walls connecting the ribs at intermediate points, chambered end sections connecting the ribs at the ends thereof, passages in the cross walls for connecting the air openings, passages in the cross walls adjacent the end sections for connecting the air openings with the chambered end sections, and openings in the side and end walls of said end sections for connecting the chambers therein with the space surrounding the grate bar whereby air within theair openings may escape therefrom, thru the chambers and openings at the end of the bar without having to force its way thru the'fuel above the central portion of the grate bar.

2. An elongated grate bar comprising a plurality of elongated spaced deep ribs separated by elongated deep air openings, cross walls con necting the ribs at intermediate points, chambered end sections connecting the ribs at the ends thereof, passages in the cross walls for connecting the air openings, passages in the cross walls adjacent the end sections forconrlecting the air openings with the chambers or spaces within the end sections, and openings in the side and end walls of said end sections for connecting the chambers with the space surrounding the grate bar, whereby air within the air openingsmay escape therefrom, thru the chambersand openings at the end of the bar, without having to force its way thru the fuel above the central portion of the grate bar.

3. An elongated grate bar comprising a plurality of parallel, elongated, longitudinally extending spaced ribs, separated by parallel, elonof the latter, longitudinally extending passages in the transverse walls of the end sections adjacent the ends of said first mentioned ribs for connecting the end air openings with the chamber or hollow space within the end sections, and openings in the chamber'walls of the end sections for connecting the chambers with the space surrounding the grate bars, whereby air within the air openings may escape therefrom thru the passages, the'chambers and the openings without its being compelled to find a way thru the bed of fuel above the central portion of the grate bar.

4. An elongated grate bar comprising a plurality of parallel, longitudinally extending, elongated, deep, spaced ribs, separated by parallel, elongated, deep air openings, transverse walls connecting the ribs, hollow end sections comprisinghollow enlarged longitudinal ribs and hollow end transverse walls, connecting and traversing the ends of the first mentioned ribs, longitudinally extending passages in said first mentioned transverse walls for connecting the air openings at adjacent ends of the latter, longitudinally extending passages in the transverse walls of the end sections adjacent the ends of said first mentioned ribs for connecting the end air openings with the chamber or hollow space Within the end sections, and openings in the chamber walls of the end sections for connecting the chambers with the space surrounding the grate bar, whereby air within the air openings may escape therefrom thru the passages, the chambers and the openings without its being compelled to find a way thru the bed of fuel above the central portion of the grate bar.

5. An elongated grate bar comprising a plurality of parallel, longitudinally extending, elongated spaced ribs, separated by parallel, elongated air openings, transverse walls connecting the ribs, hollow end sections comprising hollow enlarged longitudinal ribs and hollow end transverse walls, connecting and traversing the ends of the first mentioned ribs, longitudinally extending passages in said first mentioned transverse Walls for connecting the air openings at adjacent ends of the latter, longitudinally extending passages in the transverse walls of the end sections adjacent the ends of said first mentioned ribs for connecting the end air openings with the chamber or hollow space within the end sections, and openings in all of the chamber walls of the end sections for connecting the chambers with the space surrounding the grate bar, whereby air within the air openings may escape therefrom thru the passages, the chambers, and the openings Without its being compelled to find a way thru the bed of fuel above the central portion of the grate bar.

6. An elongated grate bar comprising a plurality of parallel, longitudinally extending, elongated, deep spaced ribs, separated by parallel, elongated, deep air openings, transverse walls connecting the ribs, hollow end sections comprising hollow enlarged longitudinal ribs and hollow end transverse walls, connecting and traversing the ends of the first mentioned ribs, longitudinally extending passages in said first mentioned transverse walls forconnecting the air openings at adjacent ends of the latter, longitudinally extending passages in the transverse walls of the end sections adjacent the ends of said first mentioned ribs for connecting the end air openings with the chamber orhollow space within the end sections, and openings in the side and end walls of the end sections for connecting the chambers with the space surrounding the grate bar, whereby air within the air openings may escape therefrom thru the passages, the chambers and the openings without its being compelled to find a way thru the bed of fuel lying on the central portion of the grate bar.

GEORGE G. MARX. 

